How to prune plants

Pruning is one of the most misunderstood and feared subjects in gardening. But there's little to worry about. Few plants will be killed by cutting bits off - more likely they will grow even stronger. Here's how to go about it.

How to prune plants

You will need:

  • Secateurs
  • Long-handled pruners
  • Pruning saw
  • Leather gardening gloves
  • Methylated spirits

Time to complete job: Variable
Approximate budget: Negligible

The amount you prune a plant depends on the type and when it flowers. Shrubs which flower in spring or early summer are flowering on last year's growth and benefit from removing some of the stems just after flowering. This encourages new growth which will flower better the following year. Late summer flowering shrubs, such as Buddleia (Buddleja Davidii), flower on the current year's growth.

Plants grown for their foliage or bark, such as Cornus, produce a better display from new growth. Both these can be cut hard back each spring.

  • Step 1: Remove diseased & damaged wood

    Step 1: Remove diseased & damaged wood

    It's not essential to remove dead branches but it can make plants look better and encourages plants to redirect growth into new vigorous shoots which will flower better. If caused by disease, however, cut out completely to live healthy wood lower down the plant.

    Prune as illustrated, just above a healthy bud.

    Tip: Clean blades with methylated spirits between plants to avoid spreading disease.

  • Step 2: Remove unwanted growth

    Step 2: Remove unwanted growth

    If blocking a view or path, unwanted growths can be cut back to a main stem.

    For thick growth, the technique is as illustrated. Make a small upwards cut about 30cm (1in) from the main stem, then a downward cut to remove the weight of the branch to avoid tearing the bark. Lastly, make a single tidying-up cut leaving a small stump about 12mm (1/2in) from the main stem - no closer.

    A mass of thin shoots congesting the centre of plants can reduce air circulation and encourage mildew, so on susceptible plants remove all weak and inwards crossing growths, leaving an open centre.

    Suckers can grow after root damage to grafted plants. To remove, scrape away soil down to where they join the root and pull off. Cutting may encourage further growth.

    Sometimes variegated plants have plain green shoots. Cut out completely or they may take over the plant.

    Tip: If you have a plant growing lopsided, trim back the weak side only, reducing all shoots by about half and completely removing thin and weak branches.

  • Step 3: Use the correct tools and techniques

    Step 3: Use the correct tools and techniques

    For stems up to 12mm (1/2in) diameter, use secateurs. Up to about 37mm (1 1/2in), use long handled loppers. Use a pruning saw for thicker stems. Long-handled pruners can be used when branches are out of reach - it's safer than using a ladder!

    Tip: When pruning fruit trees do not touch the cut surface with your hands or you will leave a deposit from your skin which will enable invading organisms to take hold. Leave the cut clean and open to the air so that natural healing processes can take place.